Home Index Previous Pages Next Pages Scan of original page
With the car and engine stationary press down the brake pedal, then start up the engine while maintaining the pressure on the pedal. Immediately the engine starts, the pedal will move forward without any additional effort on the part of the driver, thus showing that the force exerted by the piston has increased the pressure on the brake. If the engine is then switched off, the driver will immediately feel an increased re-action from the pedal.

When the driver takes his foot off the pedal, the brake shoes are immediately released; the first movement of the pedal is rapid, but the last fraction is slower than is usual with an unassisted brake. Users are advised, however, not to attempt to accelerate the return of the pedal by increasing the tension of the pull-off springs because this would unnecessarily increase the pedal pressure required to obtain a given braking effect.

The power of these brakes is sufficient to enable the car to descend the steepest hills quite slowly with the clutch disengaged and the full power of the brakes remains available with the car stationary so long as the engine is kept running.

If the ignition is switched off when descending a hill the motion of the car will turn the engine and thereby will create a suction that will assist the brakes, but this assistance ceases if the car stops, unless the engine be re-started.